Mounting device for boiler casings



Nov. 26, 1940.

'. J. KUNZ ETAL.

MOUNTING DEVICE FOR BOILER CASINGS Filed Feb. 2, 1940 INVENTOR Mum/w J Ku/vz, BY Jose/ H fi? CflRE),

Patented Nov. 26, 1940 UNITED STATES 2,223,215 r MOUNTING DEVICE FOR BOILER CASI NGS Z PATENT OFFICE York, N. Y.

Application February 2, 1940, Serial No. 316,890

4 Claims.

This invention relates to casings for heat exchange apparatus and particularly to an im-- proved means for attaching casing plates to heat exchange tubes in such apparatus.

The invention will be described as'utilized in the wall of the furnace of a steam generating boiler, although it is capable of wider more general application as will be apparent. In boiler furnaces a typical wall construction includes fluid .10 circulating tubes which line'the furnace side of the wall and in back or outwardly of these tubes refractory in the form of a tile, plastic or the like, then an insulating material and finally the boiler casing. This casing is usually'made of steel ,6 sheets held against the insulation by being attached to the boiler tubes.

During operation of the furnace the wall tubes absorb heat which is transferred to the fluid therein and a tube assumes a temperature ap- 20 proximately that of the fluid. The tile backing up a tube assumes a somewhat lower temperature, the insulation is still cooler and the casi has a temperature somewhat above that of the surrounding room. Due to the differences in ex- 25 pansion between the heated tubes and the comparatively cool casing there is a relative movement and provision must be made in the fastenings which hold the casing to the tube for adequately accommodating these relative movements 30 under expansion. It is an object of this invention to provide improved means for holding the furnace casing in spaced relation with the furnace tubes which will adequately and freely allow for relative movement 35 between them.

How the foregoing, together with other objects and advantages as may hereinafter appear or are incident to my invention are realized, is illustrated in preferred form in the accompanying 40 drawing, wherein I Figure 1 is a horizontal sectional view through the wall of a furnace and shows a typical wall tube with the casing secured thereto in accordance with the present invention, the section being 45 taken on the line in Fig. 2;

Figure 2 is a sectional elevation taken on line 2-2 in Fig. 1 with the insulation and refractory of the wall removed; and

Figure 3 is a sectional elevation on the line 50 3-3 in Fig. 2.

In the drawing the numeral I designates a vertically disposed fluid circulating tube which is backed up on the side away from the furnace of the boiler by refractory l2, insulation I3 and a 55 steel sheet or plate I4 forming part of the boiler casing. Tube 40 may be provided with fins 5 t which aid in the radiant heat absorption from the furnace and also in protectingthe refractory l2. On the outer side of tube ID a channelshaped metallic member I6 is welded to the tube 5 with the longitudinal edges ll of its flanges disposed against the tube so as to parallel the major axis of the tube. The web of channel member I6 is provided with a slot l8 which extends inwardly from one end edge along its major portion. As 10 illustrated slot H3 is open at the bottom end edge of the channel.

Casing plate i4 is provided on its innerside with a stiffening member I9 having a flange extending toward-the inside of the wall and a plate lies opposite said stiffening member on the outside 'of the casing. Abolt 2| having its head 22 located within the U of channel l6 passes through plate 29, casing I4 and stiffener l9, these three members being clamped firmly together in spaced relation to tube II] by nuts 23 and washers located on the bolt at opposite sides of plate I4. A plate or shoe 25 is slidably guided within channel member 6 and is so shaped and proportioned that it does not turn therein. Shoe 25 is provided with a transverse slot 26 of a width or height to fit snugly but slidably over a squared portion 2'! directly under the head 22 of bolt 2| so \as to prevent turning of the latter while permitting movement of the bolt transversely in the slot. With the parts in assembled relation slot 26 in shoe 25 intersects slot I8 in channel member 56 at right angles and parts of both register with bolt 2i passing therethroug-h.

It will be seen that in this construction the bolt 2| is rigidly clamped at right angles to casing plate l4 and its stiifening members and is also held at right angles to the tube l0 and the associated channel member I6. Difference of expansion vertically between tube Illand easing plate I4 is accommodated by vertical sliding movement of the bolt 2| and shoe 25 relatively to channel l6 and tube I0 as permitted by slot 18. The relative horizontal difference in movement between the tube Ill and casing plate I4 is accommodated by a transverse movement of the bolt 2| in slot 26 of shoe 25. With this construction it is impossible for bolt 2| to cook at an angle with respect to casing plate I4 and therefore with respectto tube HI and its channel member It, with the result that the bolt is free toslide in both directions and will not bind.

As illustrated in the drawing it is assumed that the tubes Ill and easing plate M are suspended from above. When cold the bolt 2| would 55 this purpose, as best shown in Fig. 3, the tile 12 v be positioned near the lower end of the slot I! in channel It. when heated the tube expands downwardly more than the casing so that the bo1t'2l moves upwardly in the slot I8. Should the tube and casing plate be supported from below, the whole assembly would be inverted for then the tube would expand upwardly more than the casing plate. The relative positions of slot and bolt may thus be accommodated to the relative expansions in any direction. Obviously the relative positions of the bolt 2| within the slot 26 of shoe 25 may be shifted to one side to suit a cold position. 1

Our improved design has the further advantage in that the tubes can be removed into the furnace without the necessity of dismantling either the tile, the insulation or the casing. For

has been omitted for a distance below the channel member It thus forming a pocket into which the bolt head 22 and shoe 25 can be lowered after the outside nut 22 has been loosened. Since the insulation I3 is rockwool or similar yieldaole material, the inner end of bolt 2| may be canted downwardly so that shoe 25 disengages channel member l6, thereby releasing tube ill for removal. The channel member may be fastened to two adjacent tubes, particularly if the tubes are without fins and closely spaced, such as bifurcated tubes, the legs of the channel being welded to each one of the tubes. The channel then serves as a spacing and stiffening member between the adjacent tubes as well as a part of the yielding spacing means for the tubes from the casing.

Although an illustrative embodiment of our invention has been described in detail, there are many changes and variations that may be made without departing from the invention and therefore it .is desired and intended to include all such changes and variations within' the scope of the appended'claims. r

What we claim'is:

1. In combination with a heat exchange tube; a channel member attached along the longitudinal edges of its flange portions tosaid tube and having its web or base portion formed with a slot extending inwardly from one end edge thereof; a

v shoe slidably mounted on the inner face of the web of said channel and restrained from turning movements in said channel, said shoe being provided with a slot intersecting and extending at right angles to the slot in the web of said channel; and afastening bolt disposed with its head located within said channel and having a shank extending through aligned portions of the slots in said shoe and channel and formed adjacent' said head with a portion so fitting the slot in said shoe as to inhibit turning of the bolt while permitting relative movements of said bolt and shoe in the direction of the major axis of the slot in the latter.

2; In combination with a heat exchange tube; a channel member attached along the longitudinal edges of its flange portions to saidtube and having its web or base portion formed with a slot extending inwardly from one end edge thereof; a shoe slidably mounted on the inner face of the web of said channel and restrained from turning movements in said channel, said shoe being provided with a slot intersecting and extending atright angles to the slot in the web of said channel; and a fastening bolt disposed with its head located withinsaid channel and having a shank extending through aligned portions of the slots insaid shoe and channel and formed adjacent said-head with a portion so fitting the slot in said shoe as to'inhibit turning of the bolt while permitting relative movements of said bolt and shoe in the direction of the major axis of the slot in the latter, a structural member having an aperture through which the shank of said bolt extends; and nuts on said bolt positioned at opposite sides of said structural member for securing it in spaced relation to said tube.

3. .In a wall structure including a substantially vertically disposed heat exchange tube; .a channel member having the longitudinal edges of its flange portions welded to said-tube parallel to the axis thereof and having its webportion formed with a vertical slot extending from one end edge thereof parallel to the longitudinal axis of said tube; a shoe slidably mounted in said channel and restrained from turning movements in said channel. said shoe being formed with a horizontally extending slot intersecting the vertical slot in the web of said channel; a bolt disposed with its head located within said channel and having a shank extending through aligned portions of the slots in said shoe and channel and formed adjacent said head with a portion so fitting the slot in said shoe as to inhibit turningof the bolt while permitting relative-transverse movements of said bolt and shoe; a casing plate having an aperture throughwhich said bolt shank extends; nuts on said bolt positioned at opposite sides oi said casing plate for mounting it in spaced relation to said tube; and filling material between said channel and said casing plate.

4. In a furnace wall having water cooled furnace tubes arranged on the inner face and a casing on the outer face, spacing means between the tubes of the casing comprising members fastened to said tubes, each member having a portion in a plane parallel to said casing, a slot in said portion extending parallel to the longitudinal axis of said tubes, a shoe constructed and arranged to slide in said slot in the direction of said axis but restrained from revolving about or inoving in the direction of an axis at right angles to the plane of the casing, said shoe having a slot extending at right angles to the slot in said member and aefastening bolt disposed with its head located on the side of the shoe toward the tubes and having a shank extending through the slot of the shoe and formed adjacent said head with a portion fitting the slot in said shoe to prevent revolving the bolt while permitting movement of said bolt in the direction of the major axes of 'WIILIAM J. KUNZ JOSEPH P. CAREY. 

